W: The volcanic ash from the eruption of Mount Saint Helens certainly caused a lot of damage, didn’t it
M: It did, but not as much as experts have predicted. It seems to have had a beneficial effect as well.
W: Really But were crop losses great
M: Yes, However, since the weather following the eruption was unexpectedly good, some crop yields remained steady or even increased beyond normal expectancy levels.
W: I’m glad to hear that. But what was the beneficial effect you mentioned
M: A mass destruction of various insect populations.
W: How could the ash kill insects without effecting people too
M: It’s highly abrasive and quickly wears away the outer wax layer, protecting insects bodies. Removal of that layer causes the insects to lose body moisture by evaporation, the result is usually lethal.
W: How about that Sounds like an effective yet natural insecticide.
W: The volcanic ash from the eruption of Mount Saint Helens certainly caused a lot of damage, didn’t it
M: It did, but not as much as experts have predicted. It seems to have had a beneficial effect as well.
W: Really But were crop losses great
M: Yes, However, since the weather following the eruption was unexpectedly good, some crop yields remained steady or even increased beyond normal expectancy levels.
W: I’m glad to hear that. But what was the beneficial effect you mentioned
M: A mass destruction of various insect populations.
W: How could the ash kill insects without effecting people too
M: It’s highly abrasive and quickly wears away the outer wax layer, protecting insects bodies. Removal of that layer causes the insects to lose body moisture by evaporation, the result is usually lethal.
W: How about that Sounds like an effective yet natural insecticide.
The second-largest volcanic eruption of the 20th century, and by far the largest eruption to affect a densely populated area, occurred at Mount Pinatubo in Philippines on June 15, 1991. The eruption produced high-speed massive falling of hot ash and gas, giant mudflows, and a cloud of volcanic ash hundreds of miles across. The impacts of the eruption continue to this day.
A huge cloud of volcanic ash and gas rose above Mount Pinatubo, Philippines, on June 12,1991. Three days later, the volcano exploded in the second-largest volcanic eruption on Earth in this century. Timely forecasts of this eruption by scientists from the Philippine Institute of Volcanology and Seismology and the US Geological Survey enabled people living near the volcano to evacuate to safer distances, saving at least 5000 lives.
On July 16,1990,a magnitude 7. 8 earthquake (comparable in size to the great 1906 San Francisco, California, earthquake) struck about 60 miles (100 kilometers) northeas
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